How Training My Traps Fixed My Sore Shoulders When Rucking

When I first got into rucking, I genuinely thought I had everything dialled in. My pace was solid, the distances were manageable, and I was gradually increasing the weight in my rucking backpack. On paper, it all made sense.

But every time I finished a ruck, my shoulders were in bits.

Not just a mild ache, but that deep, lingering soreness that sticks around for hours and makes you dread putting the bag back on the next day. At first, I did what most people do. I blamed the gear. I convinced myself it had to be the backpack, the straps, or maybe just something I needed to “get used to.”

So I adjusted everything. I tightened straps, shifted weight, experimented with different setups, and even considered whether a weighted vest might be a better option. But no matter what I changed, the result was always the same. My shoulders took a beating.

It turns out, the problem wasn’t what I was carrying. It was what I wasn’t.

The Missing Piece: Trap Strength

What I eventually realised, through a bit of trial and error, is that my traps simply weren’t strong enough to handle the load I was asking them to carry. When you’re rucking, especially with a heavier backpack, your upper traps are constantly working to stabilise the weight, support the straps, and maintain your posture. If that support system isn’t strong enough, the load has to go somewhere. In my case, it was dumping straight into my shoulders.

Once that clicked, the solution became obvious. Instead of endlessly tweaking my setup, I needed to build the muscle that was actually responsible for carrying the load. I shifted my focus towards training my traps properly, and within a few weeks, the difference was noticeable.

The soreness started to fade, my posture improved under load, and rucking began to feel far more controlled and sustainable. It wasn’t that the weight got lighter. I just became better equipped to carry it.

Why Strong Traps Make Rucking Easier

The traps play a much bigger role in rucking than most people realise. They act as a kind of natural support system, helping to distribute the load across your upper body rather than allowing it to concentrate in smaller, more vulnerable areas like the shoulders.

As they get stronger, everything starts to feel more balanced. The pressure from the straps becomes less intrusive, your posture becomes easier to maintain, and you can handle heavier loads without feeling like your shoulders are being ground down over time.

This is especially noticeable when switching between rucking backpacks and weighted vests. A backpack places more direct demand on the traps because the load sits higher and pulls down through the shoulders. A weighted vest distributes the load more evenly across the torso, which can feel more comfortable initially. However, once your traps are properly conditioned, both options become far more manageable, and you are no longer limited by shoulder fatigue.

How I Started Training My Traps

I didn’t reinvent my training or add anything overly complicated. The key was consistency and focusing on movements that directly target the traps while also carrying over to real-world load-bearing.

The exercises that made the biggest difference for me were:

• Dumbbell shrugs, focusing on control and a strong squeeze at the top of each rep

• Barbell shrugs, allowing me to go heavier and build more overall strength

• Farmer’s carries, which closely mimic the demands of carrying weight over distance

• Dead hangs, helping to build endurance through the shoulders and upper back

• Upright rows, used more as a secondary movement for added volume

What mattered most wasn’t variety, but intent. I made sure I was actually engaging my traps properly, rather than rushing through reps or letting other muscles take over. Over time, that consistent effort translated directly into better performance when I was out rucking.

The Difference It Made

Once my traps caught up with the demands of rucking, everything changed. The shoulder pain that used to feel inevitable simply stopped being an issue. I could load up a heavier rucking backpack or throw on a weighted vest and focus on the session itself, rather than worrying about how uncomfortable it was going to be afterwards.

More importantly, it made rucking enjoyable again. Instead of feeling like something I had to push through, it became something I could lean into and actually improve at.

If you’re dealing with sore shoulders every time you ruck, it’s worth stepping back and looking beyond your gear. While a good setup does matter, it won’t compensate for a lack of strength in the muscles that are actually supporting the load.

For me, building my traps was the missing piece. It turned rucking from a constant battle with discomfort into a much more controlled and sustainable form of training.

Sometimes the fix isn’t external. It’s physical. And once you address that, everything else starts to fall into place.